Kitchen Electrics - Advice Required Please?

Hello there,
I'm currently planning the cable runs for our new kitchen extension, as
the plasterer is here on Monday!!
I have explained to SWMBO that I need to know where the Dishwasher,
Washing Machine, Dryer, Fridge, Freezer are to be located to allow me
to place the switches above worktop height to isolate the behind
cupboard sockets
SWMBO isn't impressed with having these switches above the worktop...
As I have plenty of spare ways in the consumer board, (I have installed
2 * 12way split MK boards) can I run a single radial 2.5mm cable to
each outlet and use the MCB as a means of isolation on the rare
occasion it is required?
If I need the isolating switches, can I supply double socket rather
than single outlets?
Secondly, but on the same vein,
We have a duel fuel , gas / electric range cooker which needs a supply.
I intended running a 6MM^2 to a outlet behind the cooker. Do I need an
above worktop switch? Can it be inside a cupboard? Can I use the MCB
as a means of isolation?
Many thanks for any help.
(just on the way to waterstones to collect on-site guide to the regs)
p.s. (sorry about this)
can I run cable horizontally between above worktop sockets?
How close to the sink can electric sockets be?
Adrian

No, because
(a) MCBs are single pole, and isolation requires double pole isolation
(b) the MCBs are not under the control (within sight) of anyone working
on the appliances, so you would have to use lock-off MCBs
However plug and (unswitched) socket are accepted method of isolation. I
would have the sockets in the cupboards below the worktop, next to the
gaps for the appliances. Means you don't have to pull the appliance out
to change a fuse. Then you would'nt need isolating switches.
You could also use a gridswitch panel with 20A DP switches and fuses to
provide isolation to a number of unswitched, unfused 15A sockets (one on
each MCB circuit). This also allows you to put the appliances on a
non-RCD protected circuit. (Unless you have TT earthing, in which case
you can put them on the 100mA rather than the 30mA side of a split load
CU). You can get the gridswitch panel engraved with designations for the
switches.

Subject to the constraint that double sockets aren't necessarily rated
at 2 x 13A full load. AIUI they only have to be rated at 20A.

Yes
> Can it be inside a cupboard?
Needs to be within 2m of the cooker; I would prefer NOT to be in a
cupboard, as someone unfamiliar with the house might need to switch the
appliance off quickly in an emergency.

No; see above.

Yes.
Close as you like provided they are suitable for the environment, ie
place them well out of splashing distance.
If you have a Building Regs application for your extension, have you
included the wiring on that application - it will therefore be compliant
with Part P?
Owain

Thanks both for quick reply..
I hadn't considered the MCBs being single pole
I like the idea of a Grid switch, but hadn't considered feeding each DP
switch from a single MCB.
Can the Grid Switch be out of sight, in the pantry? or does it have to
be nearby the appliance?
The building Regs were applied for / passed 4 years ago, and this is
the last job on the extension (apart from the bathroom happening in
parrallel). I understood that as I had started the extension Part P
didn't apply?
regards
Adrian

If you make a short ring circuit just to supply the appliances in the
kitchen, then you can use one properly rated MCB as the safety breaker
device for it.
The ring circuit can have all the remote switching connected on it, and then
spaced around the room to suit. From the remote switching to "un-switched"
sockets below the worktop don't need separate fused connector units in this
configuration.

The remote switching is best kept in a place which is easily reached in an
emergency, and in a place convenient for use when maintaining the
appliances.
If an engineer has to walk back and forth to a switch while he works on an
appliance, then it isn't very convenient.

For your own sake, it would be better to keep the new installation up to
current requirements, and not to try and retro-fit anything.

Thanks for the replies on this,
I have decided to go for a MEM Gridswitch in the corner of the kitchen,
with DP switches for each appliance.
I've fed a 2.5mm T&E to each from separate MCBs in the Consumer unit.
probably overkill, but I'm happy I've met / exceeded requirements
Regards
Adrian

The remote switching for these low level un-switched sockets can all be done
from one point. The sockets can be run on radial wiring to the exact
positions for the appliances from there.
The sockets should really be un-switched to denote they are remotely
switched though, and the isolator switches should be double breakers to make
them safer.

The best method is to have the isolator switch break both poles to the
circuit, which an MCB doesn't do.
I've never heard of any problems having a two gang socket fitted to the one
remote switch, but they socket does need to be un-switched to mark it as
having remote isolation switching on it.

You really do need at least a double pole breaker switch near at hand in
case of emergencies, and for convenient use of isolation by a maintenance
engineer.
The use of double pole isolation means the appliance can be worked on
without the neutral conductor still having some capability to cause a shock.
So an MCB isn't really a good method of totally safe isolation because it
only breaks the Live supply side of the circuit.

If you intend to drill through the walls to install hanging racks and
things, then it isn't a really good idea to have long horizontal cable runs
around the kitchen walls. This is especially so if you sell the house on,
and the new owner has racks to hang on the walls.

The socket can actually be in the sink if it is designed for the job, but
the best rule of thumb is "Not in a position that can be easily splashed
with copious amount of water from the sink".

The switches aren't actually required at all, except for the cooker. You
only need a switch if you connect the appliance directly into an FCU. Even
in that case, the switch does not need to be accessible.
The means of isolation required is not emergency switching and can consist
of either a DP switch OR a plug/socket arrangement. You must be able to
effect the isolation (i.e. pull the plug) without disassembling the
appliance.
Christian.

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